ElrA and AUF1 differentially bind cyclin B2 mRNA.
In Xenopus embryos, maternal cyclins drive the first 12 cell divisions after which several cyclins are terminally degraded, including cyclin B2. Cyclin B2 disappearance is due to transcription-mediated mRNA deadenylation at the midblastula transition, when transcription initiates and the cell cycle lengthens. To further define the mechanism, we characterized proteins capable of binding cyclin B2 3'UTR. We show that ElrA and AUF1 compete for binding to regions containing cytoplasmic polyadenylation elements (CPEs), with AUF1 binding increasing at the midblastula transition. Deletion of both CPEs abrogates polyadenylation but has no effect on deadenylation or binding of ElrA or AUF1. Overexpression of ElrA or AUF1 does not alter cyclin B2 mRNA stability. These results show that ElrA and AUF1 bind to cyclin B2 mRNA independent of CPEs and function by binding other elements.
Guo
Xun
X
Cell Biology and Physiology, University of New Mexico HSC, MSC08 4750, Albuquerque, NM 87131, USA.
Gourronc
Francoise
F
Microbiology, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, USA.
Audic
Yann
Y
Laboratoire de Genetique du Developpement CNRS-UMR6061, Universite de Rennes I, CS 34317, 35043 Rennes, France.
Lyons-Levy
Gillian
G
Cell Biology and Physiology, University of New Mexico HSC, MSC08 4750, Albuquerque, NM 87131, USA.
Mitchell
Therese
T
Cell Biology and Physiology, University of New Mexico HSC, MSC08 4750, Albuquerque, NM 87131, USA.
Hartley
Rebecca S
RS
Cell Biology and Physiology, University of New Mexico HSC, MSC08 4750, Albuquerque, NM 87131, USA. Electronic address: rhartley@salud.unm.edu.
D020413:3' Untranslated Regions / Q000378:metabolism*; D000818:Animals; D001667:Binding, Competitive; D019926:Cyclin B / Q000096:biosynthesis*; D056765:Cyclin B2; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D / Q000235:genetics / Q000378:metabolism*; D026723:Polyadenylation; D020871:RNA Stability; D012261:Ribonucleoproteins / Q000235:genetics / Q000378:metabolism*; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism*; D014982:Xenopus laevis / Q000235:genetics / Q000378:metabolism*
D020413:3' Untranslated Regions; D019926:Cyclin B; D056765:Cyclin B2; C480172:ELAVL1 protein, Xenopus; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D; D012261:Ribonucleoproteins; D029867:Xenopus Proteins; C523014:ccnb2 protein, Xenopus